Composite beam axial load

[ukengineer58]

Hi I have a composite beam that will be under bending and axial load as it forms part of floor bracing. Does anyone know how to solve? I can't find anything guide wise. Do u treat as a non composite and use interaction formulas, but based on the composite bending capacity?

 

[WillisV]

Though not correct from a pure mechanics based approach, the safe bet would be to treat as composite for flexural considerations and as bare steel for the axial load, and then use interaction formulas as you suggest. This is the simplified approach recommended in the 2010 AISC Commentary to Chapter I.